Bill Gates, the founder of Microsoft, announced that he will stop day-to-day running of the firm by July 2008.
Mr Gates founded the company in 1975, with childhood friend Paul Allen (bottom right), after dropping out of University.
Unlike its rivals, such as Apple, the company focused on making software.
More than 90% of desktop computers around the world now use a version of Microsoft Windows.
The next version of Windows, known as Vista, has been plagued by setbacks but is due out this year.
Windows software has made Mr Gates the richest man in the world with an estimated wealth of $51 billion (£27 billion).
He says he now plans to spend more time focusing on the philanthropic Bill and Melinda Gates Foundation.
The foundation tackles global health and education problems and is supported by U2 frontman Bono.
Mr Gates's Successor as chief software architect at Microsoft is industry veteran Ray Ozzie.
Mr Gates will remain as chairman of the firm he started over 30 years ago when he steps down in 2008.